Source Note: Cy, DNA, RG 45, Entry 517B. Someone went through and crossed through several misspelled words and handwrote the correctly-spelled word either on top of the misspelling or as an interlineation. Where the original misspelling could be read, the editors have included it as a cross through followed by the corrected spelling in angle brackets; where the original misspelling is unreadable, the editors have included only the corrected version in angle brackets.

Footnote 1: Lt. Cmdr. John H. Roys, who had been sent from Washington to serve as a liaison officer with British Naval Intelligence. “N.C.T.” was Sims’ Chief of Staff, Capt. Nathan C. Twining. “Q. 24” was presumably the code used to transmit this message.

Footnote 2: In the report of 6 October, Sims explained that Class B meant approximate location while Class A was exact location. Class C is presumably a captured vessel.

Footnote 3: Luce Bay is in Wigtownshire, southern Scotland.

Footnote 4: While several German U-boats were sunk around this time, none was sunk by depth charging. Kemp, U-Boats Destroyed, 35-37.

Footnote 5: H.M.S. Begonia, which had been converted to a Q-ship (disguised merchantman) sank in a collision with a German submarine. “Flower Cless Sloop,” Battleships-Cruisers.co.uk, Accessed on 27 September 1917, https://www.battleships-cruisers.co.uk/flower.htm.